Thanks for taking the time to open a bug report!

Describe the bug
My server crashed due to it idk how it never gave such errors in my life and no editing was dont on any item when it crashed
i have 2 items 1 survival menu 1 temp fly item no edition was happening during the crash and the plugin was on latest version
Please complete the following information:

• Resource Version v5.2.1
• Server Version purpur 1.16.5

Additional context
Pls resolve it
2021-05-07-1.log

Already confirmed to be resolved, please update to the latest snapshot.

Link; https://ci.craftationgaming.com/job/ItemJoin/707/
Remember to remove your old ItemJoin.jar file

tnx dude